1. Field of the Invention
The present invention relates to a recording apparatus that transfers ink from an ink ribbon onto paper with a recording head on the basis of image information.
2. Description of the Related Art
A recording apparatus that forms an image (including letters and symbols) on a recording medium with a recording head on the basis of image information is used as a printer, a photocopier, a facsimile, or a scanner, or in a multifunction device or a system. As an example of such a recording apparatus, a thermal transfer recording apparatus that heats and transfers ink applied to an ink ribbon onto paper (a recording medium) with a recording head (thermal head) and thereby forms an image, may be used. In this thermal transfer recording apparatus, unlike other binary recording technologies, such as an ink jet recording apparatus, a pixel can have a wide range of gradation. Therefore, in step with the recent advancement of digital cameras, a thermal transfer recording apparatus has received much attention, particularly as a printer for a natural image.
In addition, there is known a system such that a printer is directly connected to an image pickup device, such as a digital camera. The printer can perform printing out without using a device that processes image information (such as a computer). Such a system makes it possible to print out the image information from a digital camera or a digital camcorder easily and photographically. Therefore, a thermal transfer recording apparatus has increasingly received much attention. Consumers want to carry a printer together with a digital camera, and compactness is an important selling point of a printer (recording apparatus).
As a method to reduce the size of a thermal transfer recording apparatus, a paper cassette containing paper and a ribbon cassette containing an ink ribbon are loaded adjacent one another in the apparatus body, and the wasted space is thereby reduced. Japanese Patent Laid-Open No. 2000-108442 discloses a printer in which a cassette for recording paper and a cassette for an ink ribbon are loaded so that they abut each other. FIGS. 9 to 11 show a common thermal transfer recording apparatus in which a paper cassette and a ribbon cassette are loaded so that they abut each other. FIG. 9 is a vertical sectional view showing a conventional recording apparatus with paper and an ink ribbon unused. FIG. 10 is a vertical sectional view showing the recording apparatus of FIG. 9 in recording operation. FIG. 11 is a vertical sectional view showing the recording apparatus of FIG. 9 with the paper in the paper cassette and the ink ribbon in the ribbon cassette used up.
In FIGS. 9 to 11, the recording media loaded in the paper cassette 102 are cut sheets 101. One end of an ink ribbon 103 is fixed to a supply shaft 104 and the other end is fixed to a take-up shaft 105. The ink ribbon 103 is wound on the supply shaft 104 and/or the take-up shaft 105. The ribbon roll 103a on the supply shaft 104 is housed in a supply side ribbon chamber 106a, and the ribbon roll 103b on the take-up shaft 105 is housed in a take-up side ribbon chamber 106b. The supply side ribbon chamber 106a and the take-up side ribbon chamber 106b are joined by a joining member and constitute a ribbon cassette 106.
When recording is performed, a paper feed mechanism (not shown) separates a sheet P from the sheets 101 in the paper cassette 102 and conveys it to the space between the thermal head 108 and a platen roller 109 along a conveyance path (not shown). The sheet P is further conveyed so as to be nipped between a conveyance roller pair 107. The sheet P and the ink ribbon 103 are pressed against each other between the thermal head 108 and the platen roller 109. In synchronization with the conveyance of the sheet P and the ink ribbon 103, the thermal head 108 is driven on the basis of image information, ink is transferred onto the sheet P, and an image is thereby formed. In the case of color recording, the sheet P is reciprocated so that color inks applied to the ink ribbon 103 are transferred onto the sheet P one over another, and a color image is thereby formed. After the recording is completed, the sheet P is discharged from the apparatus body.
In FIG. 9, both the sheets 101 and the ink ribbon 103 are unused, the paper cassette 102 is almost filled with the sheets 101, and almost all of the ink ribbon 103 is wound on the supply shaft 104. By repeatedly performing the recording operation shown in FIG. 10, the sheets 101 and the ink ribbon 103 are used up as shown in FIG. 11. In FIG. 11, the paper cassette 102 is empty, and all of the ink ribbon 103 is wound on the take-up shaft 105.
However, in the above conventional recording apparatus, with the consumption of the sheets 101, the empty space in the paper cassette 102 increases. This space is dead/wasted space. On the other hand, as for the ribbon cassette 106, there always is a space in each of the supply side ribbon chamber 106a and the take-up side ribbon chamber 106b, between the ribbon roll and the inner face of the ribbon cassette 106 from the start to the end of use of the ink ribbon 103. These spaces in the ribbon cassette 106 are also dead/wasted spaces. In conventional recording apparatus, such dead spaces cannot be eliminated nor reduced. Therefore, the space efficiency cannot be improved. This is an obstacle to reducing the size of the apparatus body.